PROJECT SUMMARY/ABSTRACT The biomedical research community is becoming increasingly aware of the importance of small molecule metabolites in the control of cellular activity in health and disease. Acquisition of the requested ThermoFisher Scientific Q Exactive Plus quadrupole-Orbitrap mass spectrometer would bring for the first time to the New York University School of Medicine the ability to perform cutting- edge LC-MS/MS analyses of small molecules for biomedical research. The requested instrument would be indispensible for the proposed research projects of 13 NIH-funded major users and several NIH-funded additional users. These projects include studies of the effects of microbial metabolites on intestinal diseases, the link between exercise-induced metabolites and human brain, studies of cardiac protection during stress, the role of catecholamines in communication between the brain and bone marrow in the regulation of hematopoiesis, studies on neurotransmitter function in modifying neural circuits to influence perception and especially on the role of oxytocin and its metabolites on maternal behavior, studies of the role of glia in neural development and disease, studies on acyl CoA, acyl carntitines, ceramides, diacylglycerides, and triglycerides in the heart and kidney as influenced by various interventions used to treat heart disease, for studies on the metabolism of pancreatic cancer, and studies into the molecular causes of other cancers, retinal degeneration, immune disorders, Barth Syndrome and diabetes. !